Put a towel on your lap and sitting on the toilet seat with the cat, do the following; Clean the ears with Q-tips but only go in as far as you can see. Clip the claws. For the face, I use a tear stain remover from the pet store. The one I like is blue and it is PPP brand. Just wet a washcloth and put some on a corner and scrub the face and ears and neck.
Spread a big bath towel on the floor of the bathroom for when she comes out of the tub.
When I shampoo the Sphynx, I use Dove liquid moisturising soap, unscented for sensitive skin (for humans). I get it at the pharmacy section of the grocery store. It works great and is very mild.
Put a bucket or a litter box full of very warm water in the bathtub and a rubber bathmat down on the rest of the floor of the tub. Hold the cat standing on the rubber mat. Take a plastic 2 cup measuring jug and pour water over the cat from the neck down. Whe you get her wet, squirt a line of soap about 2 inches on her back and with a very wet washcloth scrub her back, tail, chest, between her legs and belly.
Rinse well with jugs of water from the bucket. Put her on the towel and bundle her up. Squeeze out the wash cloth and pull a foot out from the cat/towel/bundle and clean each toenail. Do each foot. By then, she will be quite dry.
Even my squirmiest Sphynx cats, take less than ten minutes to bathe.